Browsing by Author "Chandrasekhar, Kaarthik"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Differences in ocular blood flow in glaucoma between patients of African and European descent
    (Ovid Technologies (Wolters Kluwer) - Lippincott Williams & Wilkins, 2015-02) Siesky, Brent; Harris, Alon; Racette, Lyne; Abassi, Rania; Chandrasekhar, Kaarthik; Tobe, Leslie A.; Behzadi, Jennifer; Eckert, George; Amireskandari, Annahita; Muchnik, Michael; Department of Ophthalmology, IU School of Medicine
    PURPOSE: To investigate differences in ocular blood flow in individuals of African descent (AD) and European descent (ED) with open angle glaucoma (OAG). PATIENTS AND METHODS: A retrospective data analysis was performed on OAG patients of AD and ED who were previously examined for ocular blood flow within the Department of Ophthalmology at Indiana University School of Medicine. Data analysis included blood pressure, heart rate, visual fields, intraocular pressure, ocular perfusion pressure, and color Doppler imaging of retrobulbar vessels. Color Doppler imaging measurements were performed on ophthalmic, central retinal, and nasal and temporal short posterior ciliary arteries, with peak systolic (PSV) and end diastolic velocities (EDV) as well as the Pourcelot vascular resistive index calculated for each vessel. Two-sample t tests of unequal variance were performed with P values <0.05 considered statistically significant. RESULTS: OAG patients of AD had statistically significant lower retrobulbar blood flow values than patients of ED including lower ophthalmic artery PSV (P=0.0001), ophthalmic artery EDV (P=0.0008), central retinal artery PSV (P=0.01), temporal short posterior ciliary artery PSV (P=0.0037), and nasal short posterior ciliary artery PSV (P<0.0001). No significant differences were found in terms of intraocular pressure or visual field parameters. CONCLUSIONS: Significantly lower blood flow values were identified in all retrobulbar blood vessels in AD compared with ED OAG patients. These findings suggest that the contribution of ocular blood flow to the disease process may be different in AD compared with ED OAG patients.
  • Thumbnail Image
    Item
    Should Men and Women be Managed Differently in Glaucoma?
    (Springer, 2012) Abrams Tobe, Leslie; Harris, Alon; Trinidad, Jake; Chandrasekhar, Kaarthik; Cantor, Adam; Abrams, John; Amireskandari, Annahita; Siesky, Brent; Ophthalmology, School of Medicine
    Introduction: To assess differences in associations of ocular perfusion pressure (OPP) as well as retinal and retrobulbar blood flow between men and women with primary open angle glaucoma (OAG). Methods: A total of 116 patients with OAG (age 66.9 ± 10.9 years, 70 females) participating in the Indianapolis Glaucoma Progression Study were assessed for OPP, retinal microcirculation, and retrobulbar blood flow. Confocal scanning laser Doppler flowmetry measured peripapillary retinal capillary blood flow. Color Doppler imaging measured peak systolic (PSV) and diastolic blood flow velocities and vascular resistance in the ophthalmic (OA), central retinal (CRA), and nasal and temporal short posterior ciliary arteries (N/T PCA). Bivariate Spearman correlation and multivariate linear regression analyses were performed. Results: In female patients with OAG, inferior retinal capillary flow was associated with OPP (r = 0.246, P = 0.044). In men, superior and inferior sector retinal blood flow was associated with OPP (r = -0.402, P = 0.006 and r = -0.357, P = 0.016, respectively). There was no statistically significant association between OPP and retrobulbar blood vessel flow velocities in male patients with OAG but there was an association between OA and TPCA PSV and OPP in female patients with OAG (r = 0.290, P = 0.015 and r = 0.357, P = 0.002, respectively). In female patients with OAG, multivariate regression showed no statistically significant effect of any variable on the superior retinal capillary blood flow, with CRA PSV as a sole predictor to the inferior retinal sector (partial rho = 0.302, P = 0.015) and in male patients with OAG, superior sector retinal capillary blood flow was independently associated with intraocular pressure (partial rho = -0.371, P = 0.016) and OPP (partial rho = -0.456, P = 0.002) with a trend of association with OPP in the inferior retina (partial rho = -0.301, P = 0.053). Conclusions: There was a positive linear association between retinal microcirculation and OPP in females and a negative association in males. Male and female patients with OAG may differ in their vascular autoregulation in response to changes in OPP.